Who Gives A Fish Forums

My discus keep hiding behind the filter in my 75 gallon tank. They're about 4 months old, and I've had them for 2 weeks. Water params are good, 0 ammonia, 0 nitrite, 10 nitrate, pH 6.8. Temp is steady at 84F with an Eheim heater. Tank has sand substrate, some driftwood, and a few Amazon swords. Filter is a Fluval 407. They eat frozen bloodworms and flakes but seem skittish. Any ideas why they're doing this?

Sounds like they're stressed. How's the flow on that Fluval 407? Discus don't like strong currents. Maybe try baffling the output with a sponge or turning it down. Also, check if the tank's in a high-traffic area. They might need a quieter spot. Mine chilled out when I moved them away from the hallway.

Veloce wrote: ↑Mon May 26, 2025 11:25 pm Sounds like they're stressed. How's the flow on that Fluval 407? Discus don't like strong currents. Maybe try baffling the output with a sponge or turning it down. Also, check if the tank's in a high-traffic area. They might need a quieter spot. Mine chilled out when I moved them away from the hallway.

Yep, flow could be the culprit. I'd also add more plants or decor to break up sightlines. My discus stopped hiding when I added floating plants like frogbit. Gives 'em cover without blocking light. Oh, and what's your water change routine? Frequent changes help with skittishness.

Agree with the flow and decor suggestions. Also, how many discus do you have? They're shoaling fish and need a group of at least 6 to feel secure. If you've got fewer, they'll hide more. And double-check your lighting—too bright can spook them. I use a dimmable LED set to 50%. Lastly, try adding some dither fish like cardinals. Mine stopped hiding when they had tankmates to follow.

Mine did the same thing when I first got 'em. Turned out the filter intake was too strong. I wrapped a pre-filter sponge around it, and they stopped hiding. Also, try feeding near the front of the tank to encourage them out. Worked like a charm for me.

Thanks for the tips, everyone. I'll try baffling the filter and adding more plants. I've got 5 discus, so maybe I'll add another. Water changes are 30% twice a week with Seachem Prime. I'll report back if things improve.

Good call on the water changes. Consistency is key. And yeah, bumping the group to 6 should help. Just quarantine any new additions first. Last thing you want is introducing disease. Oh, and if you're using a white background, try a black one. Made a huge difference for my tank.

Veloce wrote: ↑Tue May 27, 2025 5:20 am Good call on the water changes. Consistency is key. And yeah, bumping the group to 6 should help. Just quarantine any new additions first. Last thing you want is introducing disease. Oh, and if you're using a white background, try a black one. Made a huge difference for my tank.

Black backgrounds are clutch. Mine went from hiding to showing off once I switched. Also, try feeding at the same times daily. Routine helps them feel secure. And if you're up for it, live food like blackworms can boost their confidence.

Quarantine is a must. I lost half my group once by skipping it. Also, consider the tank's height—discus prefer taller tanks. If yours is standard, they might feel exposed. Adding taller decor like valisneria can help. And yeah, live food is a game-changer. Brine shrimp are another good option.

All solid advice. One more thing, check for reflections. Mine were hiding because they saw their own reflection in the glass. Tilted the lights slightly, and problem solved. Good luck with the tweaks!